DUBAI Saudi security forces shot dead two alleged Islamic State fighters and two others blew themselves up outside the holy city of Mecca on Thursday, the interior ministry said.

"The terrorists fired upon security forces requiring them to respond in kind to neutralize the threat, leading to the killing of two and the death of two others who blew themselves up with explosive belts," the ministry said in a statement.

State-owned Al-Arabiya TV reported that the security forces surrounded the group in the Wadi Noman area south of the city, showing images of police trucks mounted with machine guns around a walled compound.

No civilians or security forces were killed or wounded, the interior ministry said.

In an earlier, two-day security operation that ended on Sunday, two Islamic State suspects were killed and a third was wounded in southwestern Bisha province.

Saudi Arabia, the world's top oil exporter, has been hit by a spate of deadly shootings and bombings targeting security forces or its Shi'ite Muslim minority since last year. Islamic State's local branches have claimed many of them.

The group views Shi'ites as heretics but is also bitterly opposed to the wealthy Gulf kingdom's Sunni Muslim rulers, whom it regards as having betrayed Islam through close ties with the West.